The Process Hazards Analysis Program, Bridging Accident Analyses and Operational Safety

摘要

The Final Safety Analysis Report (FSAR) for the Plutonium Facility at Los Alamos National Laboratory, Technical Area 55 (TA-55) was recently revised and submitted to the U.S. Department of Energy (DOE). As part of this effort, over 70 Process Hazards Analyses (PrHAs) were written and/or revised over the 6 years preceding the FSAR revision. The TA-55 facility is a research, development, and production nuclear facility that primarily supports U.S. defense and space programs. Nuclear fuels and material research; material recovery, refining and analysis; and the casting, machining, and fabrication of plutonium components are some of the activities conducted at TA-55. These operations involve a wide variety of industrial, chemical, and nuclear hazards. Operational personnel along with safety analysts work as a team to prepare the PrHA. The PrHAs describe the process operation; identify associated hazards; and analyze the hazards, including determining hazard scenarios, their likelihood, and their consequences. In addition to identifying the interaction of the process to facility safety systems, structures, and components, operational-specific protective features are part of the PrHA. This information is rolled up to determine bounding accidents as well as preventive and mitigating systems, structures, and components. Further detailed accident analysis is performed for the bounding accidents and included in the FSAR. The FSAR is part of the Documented Safety Analysis (DSA) approved by the DOE that defines the safety envelope for all facility operations and is essentially a license to operate. The value of formal safety analyses to the daily controls on hazardous operations for worker safety is often questioned. The safety of day-to-day operations is based on Hazard Control Plans (HCPs). Hazards are first identified in the PrHA for the specific operation, then used as input to the HCP. Specific protective features important to worker safety are incorporated so that workers can readily identify the safety parameters of their work.